1. Field of the Invention
The present invention relates to a battery pack. More specifically, the present invention relates to a battery pack and a fabricating method thereof which can increase a coupling strength between a bare cell and a circuit accessory thus prevent the circuit accessory from being separated from the bare cell due to external forces like bending, twisting and falling of a battery, by forming a fixing member protruding from the upper part of the bare cell, and coupling the fixing member with a fixing member hole of the circuit accessory formed in advance by injection molding in the type of the fixing member being laid across the fixing member hole.
2. Description of the Related Art
Generally, a secondary battery is a battery capable of charging and discharging, differently from a primary battery which is not capable of charging. The secondary battery has been manufactured in the shape of a battery pack and broadly used as power supplies of portable electronic devices like a cellular phone, a notebook computer, a Personal Digital Assistant (PDA) and a camcorder.
Especially, a lithium secondary battery among the secondary batteries has high operating voltage and energy density per unit weight, thus is more suitable for potable electronic devices.
The general battery pack of the lithium secondary battery includes a bare cell capable of charging and discharging, a protection circuit board electrically coupled with the bare cell, the protection circuit board controlling charging and discharging and intercepting a circuit at the time of over charge and over discharge, and a resin molding formed as an external case by a hot melting method of filling hot melt resin in a gap between the bare cell and the protection circuit board to prevent the protection circuit board from being separated from the bare cell, to capably mount the battery pack on an external electronic device. The battery pack includes a separate holder for supporting the resin molding portion to prevent the resin molding portion from being separated from the bare cell by the external forces like bending, twisting and falling tests applied between the bare cell and the protection circuit module.
A conventional battery pack completed by resin molding uses resin of high temperature and high pressure to fill the small gap between the bare cell and the protection circuit board, and the resin of high temperature and high pressure might break down various electronic components of the protection circuit board.
Also, in the conventional battery pack completed by resin molding, an external terminal installed in the protection circuit module and electrically coupling the bare cell with the external electronic device is formed to be pad type in a flat shape. When said an external terminal of the conventional battery pack is coupled with a connection part formed in the external electronic device with surface contact, if an external shock such as falling is given to the battery, the surface contact between the external terminal of the battery pack and the connection part of the external electronic device can be cut off by the external shock. Accordingly, the instability of the electrical connection between the battery pack and the external electronic device becomes a problem.
When the pad-type external terminal of the conventional battery pack is coupled with the connection part of the external electronic device with pushing contacts, when the number of the pushing increases, a coating layer on the surface of the external terminal might peel off or crack. When such cracking of the coating layer of an external terminal of the battery pack gets serious, the electrical flow between the battery pack and the external electronic device might become out of order. Also, because the pad-type external terminal of the battery pack is disposed in the form of being exposed directly to the outside of the batter pack, it might be corroded by moisture in the air as a long period of time elapses.
Accordingly, a connector-type external terminal that is not exposed directly to the outside of the battery pack and is not coupled with the external electronic device with pushing contacts is needed. However, because the connector type external terminal has a complicated shape and a plurality of openings, it is difficult to apply the resin molding method of filling resin between the protection circuit module and the bare cell during the manufacture when the battery pack having a connector type external terminal.